1. Field of the Invention
The present invention relates to a transmittance control method of electrochromic element, particularly to a transmittance control method of electrochromic element, whereby the electrochromic element can quickly achieve a transmittance of fixed value precisely without repeated adjustment, and there is not such case happened as to influence the accuracy of its transmittance even after aging time lapse.
2. Brief Description of Prior Art
Accompanying with the rapid progress of science and technology, a variety of specific materials have been developed, among which, electrochromic element refers to a component of reversibly changing color when voltage is applied. For example, the electrochromic element changes from transparent colorless to colored state when activated. Electrochromic element is basically a multi-layer electrochemical device in its structure. When a voltage is applied to the electrochromic element, the substances within it conduct reversible oxidation or reduction reaction which leads to a phenomena of color change. The electrochromic element can be used in our daily life. If sunshine is too strong in the outside or if internal privacy is desired, this technology can be applied to change glass transmittance.
In the operation and usage, the transmittance is lowered, the light absorbance is increased and the color becomes darker if a positive electricity is input into the electrochromic element, as depicted in FIG. 10 showing schematically the oxidation reaction of an electrochromic element; on the other hand, the transmittance is increased, the light absorbance is decreased and the color becomes lighter if a negative electricity is input into the electrochromic element, as depicted in FIG. 11 showing schematically the reduction reaction of an electrochromic element. By repeatedly applying positive or negative electricity to an electrochromic element, the electrochromic element can conduct oxidation or reduction reaction so as to reach a desired transmittance.
The above electrochromic element can reach expected effect of adjusting its light transmittance by the change of inputting positive or negative electricity. However, it is found in practical implementation that the magnitude of input voltage and current might affect the rate of change and service life of the electrochromic element. Thus, the abovementioned process of repeatedly applying positive or negative electricity for conducting oxidation or reduction reaction so as to reach desired transmittance takes a long time due to repeated adjustment; and repeated change of voltage and current might cause shrinkage of its service life. Therefore, there are still space for improvement in its overall operation and implementation.
In view of the above facts, the inventor of the present invention hereby proposes a novel transmittance control method of electrochromic element according to the research and improvements conducted on the defects of conventional method, and based on his abundant experience in R&D and manufacturing activities in relevant fields for past many years, so as to achieve the purpose of better practical value.